Proper Sizing of Copper Supply Line to Cottage

Just bought new lake side cottage in Northern Michigan (a real project at a great price). Currently on a neighbor's shared well. I am going to replumb the entire cottage this spring removing the mix of galvanized, plastic and copper in favor of completely sweated copper joints and piping.

What size main copper line line should I run (1"??) with eventual branching off to 3/4" and 1/2" copper, for the future new Deep Well that I will have drilled in a year or two. Not sure what the customary supply line diameters are. Have seen a "black hose" connection at some cottages, and copper in others.

Also uncertain in which order the sediment filter, water softener and expansion tank are situated. Are pressure relief valves necessary for small cottages (600 square feet) and where are they installed in the lines? Also, can a "dog house", i.e. a roofed enclosed lean-to 2 x 4 construction, attached to the small bathroom be constructed for the above items, to also include the water heater?. It would be weather-tight as electrical supply lines are involved for the electrical water heater and water softener. All will be drained before the winter each year.

Any good suggestions for water softeners and sediment filters. Have seen both GE and Whirlpool brands at the "Big Box" stores. Are there better choices and what micron level filtration is recommended? Thank you!

The best choice for underground water lines is PE (polyethylene) pipe. It is run in one continuous piece meaning only two fittings. It comes in black or blue. Next best although I wouldn't use it is sch 40 PVC. 1" would be my choice.

The best choice for indoor plumbing is PEX. Run in a manifold type system; one continuous piece to each fixture; blue for cold, red for hot.

No prefilter for most softeners. No big box softeners, they don't last but a few years.

Pex inside is a good choice but I find the manifold system to be expensive. I much prefer a modified manifold where larger supply lines are run close to the fixture location and then smaller 1/2" lines run to each fixture. I'm also not a fan of manablcoks either because the leak.